Genetically Speaking, Race Doesn't Exist In Humans

Race doesn't matter.
In fact, it doesn't even exist in humans.
While that may sound like the idealistic decree of a minister or rabbi, it's
actually the conclusion of an evolutionary and population biologist at
Washington University in St. Louis.

Alan R. Templeton, Ph.D., professor of biology in Arts and Sciences at
Washington University, has analyzed DNA from global human populations that
reveal the patterns of human evolution over the past one million years. He
shows that while there is plenty of genetic variation in humans, most of the
variation is individual variation. While between-population variation exists,
it is either too small, which is a quantitative variation, or it is not the
right qualitative type of variation -- it does not mark historical sublineages of
humanity.

Using the latest molecular biology techniques, Templeton has analyzed millions
of genetic sequences found in three distinct types of human DNA and concludes
that, in the scientific sense, the world is colorblind. That is, it should be.

"Race is a real cultural, political and economic concept in society, but it is
not a biological concept, and that unfortunately is what many people wrongfully
consider to be the essence of race in humans -- genetic differences," says
Templeton. "Evolutionary history is the key to understanding race, and new
molecular biology techniques offer so much on recent evolutionary history. I
wanted to bring some objectivity to the topic. This very objective analysis
shows the outcome is not even a close call: There's nothing even like a really
distinct subdivision of humanity."

Templeton used the same strategy to try to identify race in human populations
that evolutionary and population biologists use for non-human species, from
salamanders to chimpanzees. He treated human populations as if they were
non-human populations.

"I'm not saying these results don't recognize genetic differences among human
populations," he cautions. "There are differences, but they don't define
historical lineages that have persisted for a long time. The point is, for race
to have any scientific validity and integrity it has to have generality beyond
any one species. If it doesn't, the concept is meaningless."

Templeton's paper, "Human Races: A Genetic and Evolutionary Perspective," is
published in the fall 1998 issue of American Anthropologist, an issue almost
exclusively devoted to race. The new editor-in-chief of American Anthropologist
is Robert W. Sussman, Ph.D., professor of anthropology in Arts and Sciences at
Washington University in St. Louis.

Sussman and his guest editor for this issue, Faye Harrison, Ph.D., professor of
anthropology at the University of South Carolina, have enlisted the talents and
expertise of anthropologists across the discipline's four subdivisions --
biological, socio-cultural, linguistics and archeological anthropology -- plus
Templeton and literary essayist Gerald L. Early, Ph.D., Merle Kling Professor of
Modern Letters in Arts and Sciences at Washington University in St. Louis, to
provide a renewed perspective on race, a topic that historically is linked
closely to anthropology.

"The folk concept of race in America is so ingrained as being biologically based
and scientific that it is difficult to make people see otherwise," says Sussman,
a biological anthropologist. "We live on the one-drop racial division -- if you
have one drop of black or Native American blood, you are considered black or
Native American, but that doesn't cover one's physical characteristics. Templeton's paper shows that if we were forced to divide people into groups
using biological traits, we'd be in real trouble. Simple divisions are next to
impossible to make scientifically, yet we have developed simplistic ways of
dividing people socially."

Single Evolutionary Lineage

Templeton analyzed genetic data from mitochondrial DNA, a form inherited only
from the maternal side; Y chromosome DNA, paternally inherited DNA; and nuclear
DNA, inherited from both sexes. His results showed that 85 percent of genetic
variation in the human DNA was due to individual variation. A mere 15 percent
could be traced to what could be interpreted as "racial" differences.

"The 15 percent is well below the threshold that is used to recognize race in
other species," Templeton says. "In many other large mammalian species, we see
rates of differentiation two or three times that of humans before the lineages
are even recognized as races. Humans are one of the most genetically homogenous
species we know of. There's lots of genetic variation in humanity, but it's
basically at the individual level. The between-population variation is very,
very minor."

Among Templeton's conclusions: there is more genetic similarity between
Europeans and sub-Saharan Africans and between Europeans and Melanesians,
inhabitants of islands northeast of Australia, than there is between Africans
and Melanesians. Yet, sub-Saharan Africans and Melanesians share dark skin,
hair texture and cranial-facial features, traits commonly used to classify
people into races. According to Templeton, this example shows that "racial
traits" are grossly incompatible with overall genetic differences between human
populations.

"The pattern of overall genetic differences instead tells us that genetic
lineages rapidly spread out to all of humanity, indicating that human
populations have always had a degree of genetic contact with one another, and
thus historically don't show any distinct evolutionary lineages within
humanity," Templeton says. "Rather, all of humanity is a single long-term
evolutionary lineage."

Templeton's analysis gives impetus to the trellis model of evolutionary
lineages, as opposed to the candelabra model, still popular among many
anthropologists. The candelabra model generally holds that humanity first evolved in Africa and then spread out of Africa into
different populations in Europe and Asia. Picture a candelabra, then imagine
three distinct populations emerging from a single stem, each of them separate
genetic entities that have not mixed genes, and thus are distinct, biological
races.

The trellis model pictures humanity as a latticework, each part having a
connection with all other parts. It recognizes that modern humans started in
Africa about 100 million years ago, but as humans spread, they also could, and
did, come back into Africa, and genes were interchanged globally, not so much by
individual Don Juans as through interchanges by adjacent populations.

"If you look down at any one part of a trellis, you see that all parts are
interconnected," Templeton explains. "Similarly, with modern molecular
evolutionary techniques, we can find over time genes in any one local area of
humanity that are shared by all of humanity throughout time. There are no
distinct branches, no distinct lineages. By this modern definition for race,
there are no races in humanity."

Out of Africa

The candelabra model often is used to justify the "out of Africa" replacement
theory, whereby modern humans descended from a single African population,
expanding out of Africa and replacing the less advanced Old World humans in
Europe, Asia and Africa.

Templeton's analysis suggests a less hostile scenario.
"Traits can spread out of Africa to all of humanity because all of humanity is
genetically interconnected," he says. "Spreading traits doesn't require
spreading out and killing off all the earlier people. They're spread by
reproducing with people -- it's make love, not war."

Sussman says one of his motivations in devoting his first issue of American
Anthropologist to race was to show the relevance of anthropology both in the
academic world and in our everyday lives.

"Historically, race has been a key issue in anthropology," says Sussman. "Since
about 1910, anthropologists have been fighting this lack of understanding of
what people are really like, how people have migrated and mixed together.

Anthropologists such as Franz Boas, W.E.B. Dubois, Margaret Mead, Ruth Benedict
and Ashley Montagu were in the forefront of warning people about the dangers of
Nazism during the '30s and '40s, yet the anthropologists' profile on key issues
in America has been so low recently that when President Clinton appointed a
committee on race in 1997, there wasn't a single anthropologist on it.

"Anthropology, in some ways, has become too esoteric. One of my goals with the
journal is to show what anthropologists are doing and how they relate to how we
think and how we live."

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